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The sedimentary sequence of La Narce du Béage Basin is one of the few natural archives covering the last 18 ka cal. BP in the French Massif Central. This paper focuses on the palaeoecological reconstruction of environmental and climatic changes affecting this shallow periglacial lake from the Late-Glacial to the Early Holocene. After field surveys and geophysical mapping, two cores (cores A and D) were extracted and dated. Plant macrofossils, pollen, non-pollen palynomorphs (NPPs) and diatom assemblages were compared within the cores to study vegetation, temperature, pH, water level and ice cover changes through time. During the Oldest Dryas (18–14.75 ka cal. BP), climatic conditions were the coldest with a short ice-free season allowing the development of periphytic diatoms only (ecologically comparable to Arctic ones). A cold and dry steppe landscape – exposed to severe erosion – comprised an herbaceous and shrub flora (e.g. Artemisia , Chenopodiaceae, Helianthemum, Ephedra, Hippophaë, Juniperus). Animal presence is suggested by coprophilous fungi. Periphytic diatoms and allochtonous pollen (Cedrus) underline windy conditions, and the possible erosion of neo-formed soils. Then, during the Bølling-Allerød interstadial (14.75–12.7 ka cal. BP), the ice-free season increased and some trees/shrubs (Salix, Betula and Juniperus) established locally within open grasslands. During the Younger Dryas (12.7–11.7 ka cal. BP) cooler conditions favoured steppe taxa again (Helianthemum, Achillea, Artemisia , Caryophyllaceae, Ranunculaceae) and erosion increased. The ice cover on the lake prevailed even if the conditions were not as cold as during the Oldest Dryas. During the Preboreal (11.7–10 ka cal. BP) Isoëtes echinospora and I. lacustris developed in the eulittoral zone of the lake, which was surrounded by a swamp forest (with Betula nana and B. pubescens). Pinus sylvestris, Betula pendula, Corylus avellana and trees from the Quercetum mixtum rapidly established in the uplands. Occurrences of Gaeumannomyces and Xylomyces fungi – both phytopathogens on broadleaved trees – and decreasing herb values indirectly hint at a close forest canopy. At the beginning of the Boreal (10 ka cal. BP), aquatic and semi-aquatic taxa developed on open water due to longer ice-free seasons (diatoms, micro-algae, Alisma plantago-aquatica, Potamogeton, Typha). The final terrestrialization towards a mire occurred as a consequence of the Holocene warming and related to water chemistry changes (acidification, eutrophication). • During the last deglaciation, a very shallow lake established as demonstrated by palaeoecological data, such as epiphytic diatoms, living on rocks. • Late-Glacial steppe landscape with severe erosion, open grassland and possible mega-herbivore presence. Arctic-like conditions. • Development of shrubs or trees during the Bølling-Allerød interstadial and reduced ice-free season. • Dry and cold conditions persisted from the Younger Dryas to the Early Preboreal. Oligotrophic flora (Isoetids) established in the eulittoral zone. • During the post-glacial warming, the lake tended to acidify. Peat flora and organic matter accumulated and led to the terrestrialization of the lake. [ABSTRACT FROM AUTHOR]

In this study, we present the full sequence of Eemian succession from the Kozłów palaeolake – one of the key sites for Eemian Interglacial in this part of Poland. In the paper, previous palynological and diatom assessments were supplemented by further pollen, Cladocera and macrofossil analysis. This enabled detailed reconstruction of a palaeolake functioning under changes of climate and other environmental conditions during MIS 5e. All identified alterations of trophy, depth and aquatic vegetation within the reservoir point to dynamic changes in early stages of lake functioning, relatively stable conditions in mid-Eemian and gradual lake shallowing starting from Caprinus phase. Thus, Kozlów palaeolake joins the noble group of sites with exceptionally well-recognized multi-proxy records of the Eemian Interglacial environment, and has the potential to become a benchmark for this part of Europe. [ABSTRACT FROM AUTHOR]

This paper presents an overview of the results obtained by collaborative use of integrative multidisciplinary investigation of a highly unique geological section discovered in the south-eastern part of the Gulf of Finland. The main aim of this study is to identify the Late Pleistocene palaeoenvironmental and palaeoclimatic changes in the study area during one of the most controversial periods in the Late Pleistocene history, which is the MIS 5. Our approach to achieving the goal is based on the investigation of feldspar-based infrared optically stimulated luminescence (IR-OSL) dated records of pollen-induced palaeoclimate and palaeoenvironmental proxies. Palynological analysis and IR-OSL dates of 29 samples for the first time produced a detailed, characterised and dated sequence of palynological zones M6 to M8 ranging from ca. 94 ka to ca. 70 ka and made it possible to determine the chronological sequence of climate changes in this interval. Representative pollen spectra from 69 samples provided convincing evidence of a warm interval of interglacial rank at least during the latter half of MIS 5. The data obtained in the present study from well-preserved deposits of the second half of MIS 5 provided a novel insight into the palaenvironmental conditions during this period. These results seem to contradict the widely held view according to which the last interglacial stage with the climate conditions similar or warmer than today corresponds to only a small part of marine isotope stage (MIS) 5 of the deep-sea stratigraphy, i.e. MISs 5e lasting ca. 11 ka, and the period from 100 ka to 80 ka is attributed to an Early Weichselian glaciation, which in Northern Eurasia reached its maximum at about 90 ka. However, the findings obtained during the present study are also convincingly confirmed by those of our previous long-term investigations of warm climate-related shell-bearing deposits of various origins from Northern Eurasia including climatically highly sensitive Eurasian Arctic palaeo-shelf area. These results indicated that the overwhelming majority of the warm climate-related dates (ca. 82%) is also concentrated in the latter half of MIS 5 in the time range between 110 ka and 70 ka. [ABSTRACT FROM AUTHOR]

In addressing the controversial issues of the Late Pleistocene paleogeography of the Caspian basin, an important role is given to the results of the spore-pollen analysis and based on them reconstructions of climate and vegetation changes in the Northern Caspian region during the development of the Early Khvalynian transgression. In this paper we present the main results of the palynological study of deposits (chocolate clays and the overlying and underlying layers from the Srednyaya Akhtuba section) of maximum stage of the Early Khvalynian transgression; the materials are illustrated by pollen diagram with the data of spore-pollen analysis and the detailed list of palynoflora recovered from the studied Lower Khvalynian sequences, and complemented with photographs of pollen belonging to the principal autochtonous taxa and, for comparison, to some redeposited palynomorphs. Palynological materials indicate subaqual (brackish marine and freshwater) sedimentation of the sediments studied in periglacial landscapes and, for the most part, under very harsh climatic conditions. The performed climate-stratigraphic reconstructions do not contradict the data of absolute dating on the accumulation of the studied deposits during the Late Valdai (Ostashkov) late Glacial period. During this interval in the territory of the study area, plant communities of the glacial climate — tundra-steppe, periglacial forest-steppe, periglacial steppe, periglacial parklands and periglacial forests — were developed. The widespread occurrence in the composition of the periglacial vegetation cover of the studied region of the yernik formations from Betula nana and shrub communities from Betula fruticosa , B. nana , Alnaster fruticosus , Juniperus , etc. testifies to the severe climatic conditions and, possibly, the existence of sporadic permafrost in the cold stages (stadials) of the Ostashkov Late Glacial period. [ABSTRACT FROM AUTHOR]

Abstract The Eocene was an interval of climate evolution, when the extreme high temperatures of the earliest Cenozoic gave way to a global cooling trend. Fine-grained lacustrine sediments of Eocene age from northeastern China represent an excellent archive to study long-term environmental and climatic changes at high-resolution. The Huadian Basin is a Cenozoic, fault-bounded basin in Jilin Province, northeastern China. Though small in area, it contains numerous oil shale- and coal-bearing layers, which provide an abundant Middle to Late Eocene palynoflora. Eighty-five palynomorph genera and one hundred palynomorph species were identified in the Huadian Formation, allowing to distinguish 4 palynozones. The nearest living relatives of the recovered palynomorph taxa suggest the presence of subtropical evergreen and deciduous broad-leaved forests during deposition of the Huadian Formation. Using the coexistence approach (CA), we calculated seven paleoclimatic parameters, which indicate a subtropical warm and humid climate with a mean annual temperature above 13.6 °C and a mean annual precipitation of at least 887 mm. However, the climate became cooler and drier during the transition from the lower Oil Shale Member to the upper Carbonaceous Shale Member. Palaeoclimatic data from the various Middle and Late Eocene basins of northeastern China (i.e., the Huadian, Fushun, Yilan, Hunchun and Jishu basins) were compared with data from North American and European basins. Middle Eocene climate in the Northern Hemisphere was generally warm and humid, and the mean annual temperature and precipitation in northeastern China were similar to those in North America, though slightly lower than those of Europe. Similar trends in temperature and precipitation on different continents support the existence of a global Mid-Eocene cooling event. This paper is the first systematic study of Middle to Late Eocene seasonality in the Huadian Basin. Our results show an apparent differentiation in both temperature and precipitation between summer and winter, supporting the view that the East Asian Monsoon was established in northeastern China already during the Middle to Late Eocene. This Middle and Late Eocene monsoon was likely driven by the development of Pacific trade winds and an alternating, seasonal high- and low-pressure system over Siberia. The climatic changes observed in our dataset, especially the precipitation changes, appear to have played an important role in controlling oil shale formation in the Huadian Basin. A warmer and more humid climate, with abundant precipitation and high subsidence rates, formed a deeper Huadian depositional lake. High productivity and stable stratification provided the abundant organic matter and favorable preservation conditions necessary for oil shale accumulation. Highlights • The Middle-Late Eocene palynoflora were firstly systematically studied in Huadian Basin. • We quantitatively estimated the Middle-Late Eocene climate based on CA method. • A globally cooler phase was recognized in the Middle Eocene. • Climate seasonality in the Middle-Late Eocene supports the EAM was already prevalent in NE China. • Changes in climate, especially precipitation, play an important role in oil shale formation. [ABSTRACT FROM AUTHOR]

The Pyrenean Lake Montcortès sediments hold the longest continuous and absolutely varve-dated record of the Mediterranean region, encompassing the last three millennia, from the Late Bronze Age to the present. The reconstruction of vegetation and landscape dynamics during this time period has advanced gradually, following the progress of absolute dating by varve counting, and has been progressively published and updated in a number of papers dealing with specific time intervals at different temporal resolutions. This paper synthesizes all these studies in a single composite paleoecological sequence constrained by a single age-depth varve model. The final resolution of this reconstruction is bidecadal, on average, but some periods have been resolved at quasidecadal (Middle Ages) and subdecadal (Modern Age to present) resolutions. The study is focused on the timing of anthropization and the further development of vegetation under climatic and anthropogenic drivers until the shaping of present landscapes. An additional advantage of Montcortès is that the local history of the Pallars region, where the lake is located, is well documented and can be easily correlated with the paleoecological record. Contrary to former interpretations of general landscape anthropization of the Pyrenees during the Middle Ages, the Montcortès catchment was irreversibly transformed by anthropic activities at the beginning of the Iron Age (ca. 750-650 BCE). From this point, the catchment underwent successive transformations due to varied human uses (fire, grazing, cereal cultivation, weed/ruderal plant expansions, hemp cultivation/retting), which have been related to the different cultural phases and sociopolitical changes documented in the local historical records. The regional forests, dominated by Pinus and Quercus , experienced four main clearance events (RD) during the Iron Age (RD1; ca. 300 BCE), the Roman Period (RD2; ca. 300 CE), the Middle Ages (RD3; ca. 1000 CE) and the Modern Age (RD4; ca. 1800 CE). The detailed trends of the last two deforestation events and their causes could be studied at a decadal resolution, which significantly improved interpretation quality in ecological terms. The potential effects of climatic changes and the eventual interactions with human activities on catchment vegetation and regional forests throughout the record have also been discussed. The Montcortès record has been compared with other records at local (Pyrenees), regional (Iberian Peninsula) and biome (Mediterranean) scales. Locally and regionally, anthropization times and further ecological trends showed significant heterogeneity according to elevation, biogeographical patterns and cultural trends. The most significant coincidence is an intensification of human pressure, as noted in forest clearing and extensive land use, during several phases of the Middle Ages. At the Mediterranean level, the Montcortès record emerges as a unique sequence for the western sector of this biome that should be complemented with similar archives from the central and eastern Mediterranean. The most promising candidates for such sequences are discussed on the basis of available Mediterranean varved records. [Display omitted] • The longest, continuous and absolutely varve-dated lake record of the Mediterranean region. • High-resolution reconstruction of vegetation/landscape trends during the last 3000 years (Bronze Age-present). • Emphasis on the role of climatic and anthropogenic drivers, their feedbacks and synergies. • Detailed correlations with local archaeological evidence and historical documentation. • A potential paleoecological reference section for the western Mediterranean region. [ABSTRACT FROM AUTHOR]

In this paper, we describe palynological assemblages in the Middle Miocene (Serravallian) Kenslow Member of the Brassington Formation at Bees Nest Pit, near Brassington, Derbyshire, U.K., and infer vegetation types and their palaeoclimate implications. The limited lateral extent of the 1.33 m-thick succession of clay and lignite, and its position surrounding fragments of a large tree trunk, suggests that the succession may have accumulated within a tree throw hole or possibly within a shallow stagnant pond, although aquatic lacustrine palynomorphs have not been identified to confirm this latter hypothesis. The stratigraphical distribution of palynological assemblages, based on 58 samples allows reconstruction of a wetland succession. Two pollen zones were identified using CONISS cluster analysis, and a predominantly warm-temperate and mixed mesophytic forest biome was recognised with Tsuga conifer pollen-types being dominant (<42%) in both pollen zones. Changes in the make-up of this forested wetland were in response to local environmental changes rather than major climatic shifts. Wetland development culminated in the formation of a relatively open shrub and reed-dominated mire which produced the lignite-precursor peat. Applying the Co-existence Approach, Mean Annual Temperature was 15.6–21.7 °C and Mean Annual Precipitation was 703–1682 mm indicating a warm-temperate to subtropical palaeoclimate, and both parameters show no significant change through the section. Findings suggest that, following the Middle Miocene Climatic Optimum, the Serravallian climate of the northwestern margin of Europe remained much wetter than Central Europe, where more arid climates have been reconstructed, and this difference may have been due to the influence of the proto-North Atlantic Current. • We present a fossil record using a lignite and clay unit from the Kenslow Member. • We present the first reconstruction of a wetlands in the UK Miocene reconstruction record. • Transition from a Tsuga -dominant mixed mesophytic forest to a wetland occurred. • Palaeoclimate variables varied little and suggested frost-free conditions. • High precipitation reconstructions were caused by the proto-North Atlantic Current. [ABSTRACT FROM AUTHOR]

Studies dealing with the reconstruction of Holocene climate change of tropical areas are scarce. Of these, multi-proxy investigations using peatlands are still absent. In this paper, we present the Holocene record of environmental changes in central–eastern Brazil reconstructed from a core sampled in Pau de Fruta mire (Serra do Espinhaço Meridional, Brazil). We combined palynological and geochemical analyses, supported by core stratigraphy, 14 C dating and multivariate statistics. The location of the mire is ideal because it is in an area which is directly associated with the South Atlantic Convergence Zone (SACZ). Six main phases of change suggested by vegetation and local and regional landscape dynamics were described. In phase I (~ 10,000–7360 cal. yr BP) the climate was very wet and cold and was accompanied by soil instability in the mire catchment (severe local erosion) and the 8.2 ka event was easily recognizable by a large increase in the deposition of regional dust. Phase II (~ 7360–4200 cal. yr BP) was characterized by wet and warm conditions, catchment soil stability and enhanced deposition of regional dust. In phase III (~ 4200–2200 cal. yr BP), climate was dry and warm and soil erosion in the catchment increased again. In phase IV (~ 2200–1160 cal. yr BP) dry and punctuated cooling was reconstructed, together with enhanced deposition of regional dust. Phase V (~ 1160–400 cal. yr BP) reflects sub-humid climatic conditions (like the current climate), the lowest inputs of local and regional dust and the largest accumulation of peat in the mire. While in phase VI (< ~ 400 cal. yr BP) sub-humid conditions continued but both local and regional erosion significantly increased. Our results demonstrate that the tropical peatlands of Serra do Espinhaço Meridional contain relevant records of Holocene climate changes, and that a multi-proxy approach offers good opportunities for a detailed reconstruction of palaeoenvironments. [ABSTRACT FROM AUTHOR]

Understanding the nature of moisture availability in the Eocene, Oligocene, and Miocene of Antarctica is imperative for climate reconstructions and for understanding the potential influence of future climate change on modern landscapes. Previous studies have used traditional palynological techniques, fossil leaf margins, hydrogen isotope leaf waxes, and palynomorph δ 13 C values to indicate changes in moisture on the southernmost continent. Here, we explore the relationship between pollen width (equatorial diameter) and climate as a potential indicator of changes in moisture availability in Antarctica, a technique that had not been widely applied previously. To date, studies of pollen grain size response to environmental stress and the applicability of using fossil pollen grain size as a climate change proxy are limited. In this paper, we explore the relationship between pollen grain size and environmental stress (desiccation intensity) and whether such a relationship can be applied to fossil pollen from Antarctica. We measured the widths of 157 modern specimens of Nothofagus spp. (the genus of Southern beech) pollen from throughout the Southern Hemisphere and compared them with mean annual precipitation records to assess the relationship between pollen grain size and moisture availability. The widths of 458 Antarctic Nothofagidites lachlaniae -complex pollen grains (from Eocene, Oligocene, and Miocene cores) were then measured and compared to other paleoenvironmental proxies to evaluate whether or not a significant trend in size variability can be associated with a change in moisture availability through geological time. Modern data show a significant relationship between decreased moisture availability and increased pollen grain size and are consistent with a previous study, providing confidence for using changes in pollen grain size as an indicator of moisture. Fossil data show a 23% increase in average pollen grain size from the late Eocene through the early to mid Miocene, indicating a decrease in moisture availability in Antarctica during this time. [ABSTRACT FROM AUTHOR]

The paper presents results of a palaeobotanical investigation of the borehole core Komorniki 97/72 from the Ruja lignite deposit, Lower Silesia. In the deposit lignites of three (2nd Lusatian, 2nd A Lubin, and 1st mid-Polish) middle Miocene groups of seams are present. The lignites of the 1st and 2nd groups are important correlation horizons throughout much of the Polish Lowlands and eastern Germany. The results of the palynological studies (spore–pollen, algae and fungi) and plant macroremains studies show that during the mid-Miocene mires' development, the vegetation was characteristic of wetlands (i.e., swamp and riparian forests, shrub bogs, and reed marshes) as well as mesophytic forests. The results were also used for palaeoclimatic investigation. The mean annual temperature (MAT), for each of the three sections, based on the coexistence approach (CA) method, was estimated in the range of 15.7–17.8 °C. Nevertheless, the frequency of thermophilous (palaeotropical and palaeotropical/warm-temperate) taxa indicate climate changes during the formation of the studied sediments. Composition of the spore–pollen spectra from the 2nd Lusatian seam (i.e., the presence of Meliaceae and Sapotaceae, which currently have pantropical distribution) show that the climate was humid and warm, close to subtropical. Later, many palaeotropical taxa disappeared, and the composition of the spore–pollen spectra indicates a warm temperate climate with slight fluctuations. Above the 1st mid-Polish seam, the climatic conditions changed in a way that did not favor the further formation of lignite deposits. These results correspond with the current understanding of climate change in the middle Miocene in Europe. • The Ruja deposit contains lignite of the three youngest groups of seams. • Middle Miocene vegetation and palaeoclimate of the Ruja area are discussed. • Palynological analysis and plant macroremains are used for the palaeointerpretations. • The results correspond with the current understanding of climate change in Europe. [ABSTRACT FROM AUTHOR]

Abstract: The accurate and consistent identification of fossil pollen is essential to allow robust inferences to be drawn with regard to past climate and vegetation change. Identifications are best achieved through the direct inspection of reference material. Most substantial reference collections are held at prestigious universities in Europe or the United States of America which can restrict access for researchers trying to advance palynology in less developed countries. Digital imaging and fast spreading access to the internet means that it is now possible to produce and disseminate high quality images from pollen reference collections. In this paper we contribute to this growing body of work by presenting images of 364 pollen taxa from West Tropical Africa both as printed plates with a key, and within an associated online searchable database. [Copyright &y& Elsevier]

Abstract: This paper describes the palynological, sedimentological and geochemical results obtained from a 6 m core taken from Lake Dajiuhu in Shennongjia Mountains, central China, spanning the last 40,000 BP. The site is located in a subtropical area which is known for harboring many endemic species. The pollen record shows that past climate changes during the Glacial allowed the persistence of warm trees and even subtropical taxa. The percentages of arboreal pollen taxa vary from 40% before and during the last glacial period to ∼60% during the Holocene. The δ13C data indicate that the dominant vegetation was composed of C3 plants. However, despite the continuous presence of tree taxa around the site, the total organic carbon indicates that the biomass was very low during the glacial period (MIS 3 and 2), related to the dominance of conifers and evergreen tree taxa, which are very low biomass producers. The total organic carbon (TOC) started to increase steadily at the end of the last glacial period (end of MIS 2), which reflects the sharp increase in the amount of Sphagnum spores recorded at the end of MIS 2, marking the beginning of the peat bog formation and the increase of the in-situ biomass. The summergreen taxa, which increased during the Holocene, may have also contributed to the TOC increase. [Copyright &y& Elsevier]

[Display omitted] • Environmental monitoring is crucial for protecting human and ecosystem health. • Honey bees (Apis mellifera) can serve as global, continuous biomonitoring species. • Colonies are resilient and accumulate or respond to stressors without collapsing. • Long-range foragers transport pollutants, pesticides, and pathogens to their hives. • A. mellifera may serve to monitor emerging threats such as climate change and AMR. Monitoring the environment for pollution, pesticides, and pathogens is crucial for protecting human, agriculture, and overall ecosystem health. Diverse strategies ranging from physical sensors to sentinel species have been used for environmental monitoring. The European honey bee, Apis mellifera , is a globally managed pollinator that can serve as a continuous biomonitoring species. During foraging, honey bees are exposed to contaminants and pathogens and carry them to their hives where they can be detected and quantified. Although individual bees are vulnerable to environmental stressors, the honey bee colony as a whole is more resilient and can accumulate contaminants or respond to them without collapsing. This allows for long-term monitoring of the colony to map contaminants in a geographical area and study ecotoxicology gradients over space and time. In this paper, we review demonstrated and proposed uses of honey bees for environmental monitoring. We focus our discussion on heavy metals, air pollutants, pesticides, and plant pathogens that can be detected in bees and their hive materials including honey, wax, and stored pollen. We present the use of gene expression, microbiome profiling, and other high-throughput methodologies to study dose-dependent exposure and increase detection sensitivity; for example, stored pollen analysis with next generation sequencing can reveal the presence of plant viruses, fungi, and invasive species earlier than traditional detection methods. Finally, we discuss opportunities for using honey bees to monitor emerging threats such as climate change and antimicrobial resistance. This narrative review highlights the versatility and potential utility of the European honey bee as a biomonitoring species for ecosystem health. [ABSTRACT FROM AUTHOR]

Abstract: The evolutionary history of Pennsylvanian tropical dryland/upland communities remains enigmatic. In this paper, we describe conifer-dominated palynofloras in a facies context from the early to mid-Moscovian (Middle Pennsylvanian) interval of the De Lutte-6 borehole (the Netherlands) that shed light on this issue. Our data suggest that, in the upper Bolsovian–lowermost Asturian part of the borehole succession, Florinites-producing cordaitaleans with subordinate tree-ferns, pteridosperms, calamiteans, and lycopsids, covered low-lying braidplains draining the rising Variscan Orogen, while Cordaitina/Latensina-producing cordaitaleans, walchian conifers and enigmatic pteridosperms mostly grew in hinterland regions (Assemblage I). At one relatively brief interval, a mire dominated by calamiteans and arborescent lycopsids developed within this braidplain complex (Assemblage II). In the mid-Asturian part of the borehole succession, following a switch from humid to seasonally-dry climates (indicated by paleosols), palynofloras associated with a shallow, but extensive, lake deposit imply that communities of walchian conifers, Cordaitina/Latensina-producing cordaitaleans, and engimatic pteridosperms covered low-lying drylands, but were cyclically replaced by lycopsid ‘ephemerals’ during short-term pluvial events (Assemblage III). Across tropical Pangaea, the climate-driven migration of diverse conifers from Bolsovian hinterlands to mid-Asturian basins coincides with (1) the more frequent appearance of conifer megafloral remains in the fossil record, (2) a gradual increase in the frequency of tree-ferns in clastic swamps, (3) a decline in the abundance of arborescent lycopsids in mires, and (4) a change from perhumid raised mires to humid planar mires in cratonic areas. We therefore highlight that the mid-Asturian (mid-Moscovian) interval is an under-appreciated event in the evolution of Pennsylvanian tropical vegetation, on a par with the better-known climate-driven floral changeovers that occurred in the earliest Kasimovian and Gzhelian–Asselian. Our palaeoecological findings also clarify a long-running biostratigraphic controversy by showing that conifer dominance in the De Lutte-6 borehole is completely consistent with its Bolsovian–Asturian age, and does not require the invocation of an unconformity separating an inferred Westphalian part of the succession from an inferred upper Stephanian/Permian part of the succession, as suggested by some earlier workers. This, in turn, emphases the importance of selecting isotaphonomic (isoclimatic) samples for biostratigraphic purposes. [Copyright &y& Elsevier]

Abstract: This study presents combined mineralogical, chemical, isotopic (87Sr/86Sr and U–Th disequilibria series) and palynological analyses on bulk sediments and on distinct mineral phases (carbonates and clays) from a 10-m-long core drilled in the southern Caspian Sea and containing a Late Pleistocene and Early Holocene record. The data allowed identifying 1) the main variations in sedimentation, 2) the processes causing these variations, 3) the modification of erosion vs weathering, and 4) the influence of climatic and/or Caspian Sea level changes in the region since the Late Pleistocene. The chemical and mineralogical results allowed the division of the sedimentary sequence into three main units and a transition zone. The lower unit (unit U1) primarily consists of silicate and carbonate-rich detritus. Sedimentation characteristics, including observation of detritus in secular equilibrium, are relatively constant within this unit and reflect mechanical erosion in a cold climate. Unit U1 probably corresponds to a glacial period when the vegetation cover was sparse and wind and river transport of pollen were strong. Subsequently, global increase in temperatures has greatly modified the sedimentation in the Caspian Sea south basin. Biogenic sedimentation is higher in units U2 and U3, and detrital inputs varied from unit U1. Variations in detrital input are likely to be caused by decreasing aeolian contribution and by relative changes in river volumes and origins. The study of the bulk sediments, clays and carbonates reflects an increase in chemical weathering since about 10 14C ka BP ago (base of unit U2), in line with an increase in the vegetation cover. Our results suggest an evolution of continental weathering conditions in the catchment area of the Caspian Sea, from dominantly mechanical/physical erosion during the cold period to a continuous increase in weathering since the Lateglacial period, as climate improved, which illustrates the strong relation between climate, vegetation cover and weathering processes. This paper also highlights how the U–Th disequilibrium series proxy, combined with other geochemical and palynological studies, could be a useful tool to record and constrain the modification of weathering regime in response to climatic and environmental changes at regional scale. [Copyright &y& Elsevier]

Abstract: This paper presents a fresh examination of a pollen profile from Ustków (central Poland), which after preliminary results was thought to span a period between the Early Eemian (MIS 5e) and the upper Pleni-Weichselian (MIS 3). The newly obtained results confirmed the age assessment of the bottom series, but revealed a much older age for the uppermost part of the profile as far back as the Rederstall stadial (MIS 5b). Palynological research showed slightly different patterns of vegetation in comparison to other sites located in Central Europe. Among them were an early Ulmus maximum coinciding with the Betula optimum in the Early Eemian, a relatively late optimum of Taxus baccata during the decline of the Middle Eemian, and a distinct division of the older part of the Late Eemian into phases of Abies-Picea and Picea-Pinus forest domination. The Herning stadial (MIS 5d) falls into a typical bipartition reflected by heathland domination during its older part and the prevalence of Juniperus thickets and Artemisia-Poaceae steppe during its younger part, which makes this succession similar to those from northern Germany. The pollen spectra reflecting the Brørup interstadial (MIS 5c) distinctly revealed an intra-Brørup cold oscillation rarely detected in profiles from Central Europe and a period of Larix dominated forests during the latest part of the interstadial (extraordinarily high percentages exceeding 15% of the total pollen sum). Local pollen taxa, together with the lithological composition of deposits, revealed that there was a water body in the area during the periods of the Late Saalian/Early Eemian transition–Middle Eemian (the decline of the Tilia phase), the Herning stadial (MIS 5d), the early Brørup interstadial (MIS 5c), and the Rederstall stadial (MIS 5b). Between these time-intervals a poor and/or rich fen and/or bog functioned. [Copyright &y& Elsevier]

Abstract: There is almost no detailed Holocene pollen data in Shandong Province. This paper reports a pollen record from a natural profile at Qingdao of Shandong Province, East China between 7250 and 3500 cal. BP, and provides new evidence for the collapse of Neolithic cultures around Central China in the middle Holocene. It reveals a subtropical deciduous and evergreen broad-leaved forest was well-developed during 7250–5900 cal. BP, representing the Holocene Maximum warm climate condition. During 5900–4550 cal. BP, pollen flora retained the main features of the former stage, but the contents for the major tree components in the flora decreased, implying an end of the Holocene Maximum warmth. From 4550 cal. BP to 3900 cal. BP, the percentage of AP (Arboreal Pollen) abruptly fell to the lowest value in the profile, inferring a distinct climate deterioration. During 3900–3500 cal. BP, a major recovery of AP is captured, indicating a possible climate change. The above mentioned climate changes are in good coherence with the local Neolithic Culture evolution. It is assumed that the cold climate during 4550–3900 cal. BP is possibly responsible for the collapse of the Longshan Culture in Shandong Province. [Copyright &y& Elsevier]

Abstract: The sequence from Abric Romaní has provided several palaeoecological studies. This paper presents a synthesis of the results yielded by palynology, including the data from the entire non-excavated deposits, and the data obtained through the study of large mammals, micromammals, herpetofauna, and anthracology from the excavated layers. The palaeobotanical studies show that the sequence is mainly related to pine forests, and near or within these dominant forests there were smaller plant formations and/or secondary species with a Mediterranean and/or Atlantic character. Nevertheless, continuous forest did not dominate the entire region. The fauna occupying the territory indicate open spaces in which seasonal grasslands proliferated, dry assemblages in sunny areas and humid ones in mountain shadows. The non-excavated archaeological layers correspond to MIS 4, initially characterized by temperate and humid conditions, and thereafter cool and humid until HS 6 and MIS 3. Afterwards, at the beginning of the MIS 3, the Dansgaard–Oeschger cycles, ∼1500 yr rapid and abrupt climatic changes, occurred during the deposition of the archaeological levels O, N, M, L, K and J. Later, these events were interrupted by a cold and dry phase, between ca 49 and 47 ka BP, which affected levels Ja, I and H, culminating with HS 5. Finally, this cold episode was followed by the Hengelo interstadial or DO 12, characterized by a temperate and humid climate identified in levels E and D. [Copyright &y& Elsevier]

Abstract: In this paper, we report 3780-m-thick Neogene deposits accumulated in the Kuqa foreland basin of southern Tianshan range, providing great potential for studying both tectonics and paleoclimatic changes. Based on palynological evidence, we discuss the paleoenvironmental changes as well as the interplay between regional uplift and climatic change in the region studied. Our results indicate that the vegetation and climatic changes from 13.3 to 7Ma were response to global climatic changes. After 7Ma, the uplift of the southern Tianshan range partially affects vegetation and climatic changes. Both global cooling and the rainshadow effect of uplifted high mountains affect the enhanced arid climate initiated ca. 5.23Ma ago. Such climatic changes are important archives in reconstructing paleoclimate of the Asian interior. [ABSTRACT FROM AUTHOR]

Abstract: High-resolution macroscopic charcoal and pollen analyses were used to reconstruct the fire and vegetation history of the Willamette Valley for the last 1200years. Presented in this paper are three new paleoecological reconstructions from Lake Oswego, Porter Lake, and Warner Lake, Oregon, and portions of previous reconstructions from Battle Ground Lake, Washington, and Beaver Lake, Oregon. The reconstructions show that prior to Euro-American settlement vegetation and fire regimes were influenced by a combination of natural and anthropogenic factors. Battle Ground Lake shows a stronger influence from climate, while Lake Oswego, Beaver Lake, Porter Lake, and Warner Lake were more controlled by human activity. However, human-set fires were also modulated by regional climate variability during the Medieval Climate Anomaly and the Little Ice Age. Fire reconstructions from Battle Ground Lake, Lake Oswego, Beaver Lake, and Porter Lake imply that fires were infrequent in the Willamette Valley 200–300years prior to Euro-American settlement. The decline of Native American populations due to introduced disease may have led to this reduction in fire activity. The prehistoric record from Warner Lake, however, indicates that fires in the foothills of the Cascade Range were more frequent than on the valley floor, at least until ca. AD 1800. The historic portions of the reconstructions indicate that Euro-American land clearance for agriculture and logging produced the most dramatic shifts in vegetation and fire regimes. All five records indicate that few fires in the Willamette Valley have occurred since ca. AD 1930, and fires today are predominantly grass fires. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents palynological evidence from the late Early Triassic (late Smithian) to the Late Triassic (Rhaetian) of the Barents Sea area: A continuous palynological succession from an exploration well (7228/7-1A) in the Nordkapp Basin (SW Barents Sea) and palynological data from a series of shallow cores drilled at the Svalis Dome (Central Barents Sea) representing selected Triassic intervals. These fully marine sediments are independently dated by marine faunas. Both records show significant shifts in the distribution of the main floral elements. Changing ratios of spore-pollen taxa, grouped as hygrophytes versus xerophytes and spores versus pollen, reveal major changes of the floras within the studied interval. One distinct turnover coincides with the Smithian/Spathian boundary where lycopsid and pteridophyte spores dominated assemblages change to pollen (pteridosperms and conifers) dominated assemblages. Lower Middle Triassic assemblages are again dominated by lycopsid spores while the assemblages from the upper part of the Middle Triassic and the lower part of the Late Triassic are characterised by dominance of coniferous pollen and show the decline of pteridosperms. In the latest Triassic fern spores are abundant and diverse. In contrast to the Middle Triassic the pollen assemblages are characterized by cycadophytes and Araucariacites. These distribution patterns are interpreted to reflect climatic changes. The presented results from Norwegian Boreal areas confirm the significant differences between quantitative distribution of specific taxa as well as diversity of major groups in plant assemblages from low and mid latitudes. The present survey opens new perspectives for more detailed comparisons and climatic interpretations of floras from the Triassic period, a time during which Mesozoic vegetation established. The major changes in the dominance of specific floral elements, especially the diversification and spreading of the conifers, can probably be related to climatic changes. [Copyright &y& Elsevier]

Abstract: This paper presents multiproxy (pollen, magnetic susceptibility, sediment chemistry) records from two maar crater lakes in the Valle de Santiago of Guanajuato, Mexico: Hoya San Nicolás and Hoya Rincon de Parangueo. Sediment cores from the two sites have basal dates of ca 11,600 and 9600cal yr BP, respectively. The San Nicolás results show that the lake desiccated several times during the Holocene, and this resulted in the selective destruction of the less resistant pollen types. A comparative analysis of data from both sites indicates that during the earliest Holocene (ca 11,600–9000cal yr BP) there were short term oscillations of wetter and drier climate; during the early Holocene (ca 9000–5700cal yr BP) it was on average wetter; during the middle Holocene (ca 5700–3800cal yr BP) drier; and during the middle to late Holocene (ca 3800–2200cal yr BP) wetter. Increasing human disturbance during the late Holocene of environment obscures the climatic record. Agricultural activities in the area began as early as ca 5700cal yr BP and intensified around 2400cal yr BP. [Copyright &y& Elsevier]

Abstract: This paper investigates changes in the vegetation and hydrology at Ljubljansko barje (Slovenia) using a multi-proxy approach (pollen, diatoms, geochemical and stable isotope analysis). During the Lateglacial Ljubljansko barje was a deep, oligotrophic lake surrounded by open woodland comprised predominantly of Pinus and Betula which in the early Holocene, when the lake became shallower and mesotrophic (Fragilaria pinnata, δ 15N~3.3‰, δ 13C~−33.7‰, C/N~7.9), was replaced by broadleaved tree taxa (Tilia, Ulmus, Quercus, Corylus) and Picea. This was followed by the spread of Fagus and after ~9200 cal yr BP Abies and planktonic and oligotrophic diatom taxa (Aulacoseira italica, Gomphonema angustum) as well as an increased allochthonous influx (silt, SiO2, Al2O3). Between ca. 6750 and 6000 cal yr BP the diatom data suggest shallower and oligotrophic conditions, whereas the stable isotope record (increased δ 13C and decreased δ 15N) indicates terrestrial input. Changes in forest composition (increase of Quercus, Alnus, Corylus) and the spread of herb taxa were probably advanced by human impact on the environment. The beginning of organic sedimentation, dated to 6000 cal yr BP, was followed by an increase of Fagus and Abies and by eutrophication and peat growth at ~5200 cal yr BP. [Copyright &y& Elsevier]

Abstract: South Africa''s winter-rainfall zone is a climatically sensitive region, lying at the interface of the earth''s temperate and sub-tropical climatic systems. Its seasonally arid climate has generally prevented the preservation of long and organic-rich sedimentary deposits, producing a spatially limited and temporally biased Quaternary record. This paper seeks to address this issue further and develop a fuller understanding of the wider climatic changes in this region during the Late Quaternary. Modern climatic data does not support the definitions of the “winter-rainfall zone” presented in previous syntheses and this factor, amongst others, may explain difficulties in resolving the palaeoenvironmental record in this region. We present palaeoenvironmental evidence from the Agulhas Plain, an area marginal to the modern winter-rainfall zone. Cored sedimentological and palynological records from two pans are integrated with previously reported records of aeolian activity, providing evidence for phases of enhanced aridity and humidity during the Late Quaternary. The record is fragmentary, which may reflect the cycling of sediment between the pans and their accompanying lunette dunes. Lacustrine sedimentary sequences dating to c. 33 ka – >47 ka provide evidence for enhanced humidity consistent with evidence in the winter and year-round rainfall zones. Increased humidity is also recorded from c. 2ka, following drier conditions than the present c. 2.7–2.5ka. Palynological evidence supports the sedimentological interpretations of pan water status and offers rare insights into the nature of the region''s unique Fynbos vegetation during the Late Pleistocene. [Copyright &y& Elsevier]

Abstract: This paper presents a multi-proxy reconstruction of the climatic and environmental changes during the Last Glacial–Interglacial transition as recorded by a sediment sequence from Lake Lautrey (Jura, eastern France). This reconstruction is based on analysis of pollen, chironomid, organic matter, oxygen-isotope, mineralogical, magnetic susceptibility and inferred lake-level data at a high temporal resolution. The chronology is derived using AMS radiocarbon dates, the position of the Laacher See Tephra (LST), and of correlation between the Lautrey and GRIP oxygen-isotope records. This data set reveals a detailed sequence of environmental changes in the Jura mountains from Greenland Stadial 2a to the early Holocene. Biotic and abiotic indicators allow the recognition of major abrupt changes associated with the GS-2a/GI-1e, GI-1a/GS-1 and GS-1/Preboreal transitions, and other minor fluctuations related to the cold events GI-1d, GI-1b and the Preboreal oscillation (PBO). They also suggest additional cooling spells at ca 14,550 and 14,350calyr BP (Intra-Bølling Cold Periods), at ca 13,500 and ca 12,700calyr BP just before the GS-1 onset, and at ca 11,350calyr BP just before the PBO, as well as an intriguing brief warming episode within GS-1 at ca 12,080calyr BP. Summer temperature increased by ca 5°C at the start of GI-1e, and by 1.5–3°C at the Holocene onset, while it decreased by ca 3–4°C at the beginning of GS-1. Major changes in local hydrology and in seasonality appear to be also associated with the GS-2a/GI-1e, GI-1a/GS-1 and GS-1/Preboreal transitions. Pollen and abiotic indicators suggest a greater sensitivity of the vegetation cover to climatic oscillations during the first part of the Lateglacial Interstadial than during the second part (after ca 13,700calyr BP), when a closed forest had been restored in this area. By contrast, the restoration of forest cover took less than 300yr after the end of GS-1. At the beginning of GI-1e and GS-1, no lag occurs (within the sampling resolution of 20–50yr) in the responses of aquatic (chironomids) and terrestrial (pollen) ecosystems, while, at the onset of the Holocene, the response of the vegetation appears slightly delayed in comparison with that of the chironomid community. Finally, the recognition of two successive tephra layers, which were deposited just before the LST at ca 12,950calyr BP and which originated from Le Puy de la Nugère (Massif Central, France), provides an additional tephrochronological tool for correlation between Lateglacial European sequences. [Copyright &y& Elsevier]

Much of our existing knowledge of Middle Jurassic paleoclimate is based on well-dated marine isotopic records that show fluctuations between warm (greenhouse effected) and cool climates. In contrast, much less is known from contemporaneous terrestrial deposits that are often difficult to correlate stratigraphically with marine successions, and are typically considered as showing regional rather than global signals. In this paper we show that the carbon-isotopic, petrological and floral record through 20 m thick coals in the Northern Qaidam Basin (NW, China) represents a relatively comprehensive northern hemisphere Bajocian (Middle Jurassic) record for terrestrial climatic change. δ13C coal values for 88 samples from the Yuqia area in Northern Qaidam Basin range from–25.3‰ to –22.5‰, indicating that C3 plants were the main coal-forming vegetation in the region during the Middle Jurassic. This isotopic variation follows fluctuations in the composition of ferns and gymnosperms, where higher ratios correspond to more negative δ13C values. The similar carbon isotope values of gymnosperms and coal from the Yuqia area indicate that the coal comprises a high proportion of organic material derived from gymnosperm taxa, which is consistent with the very high abundance of diterpenoids in coal and especially pimarane and abietane that are produced primarily by gymnosperms. Results from the coal matrix provide an opportunity to record paleoclimate changes, showing several striking and regular coal-forming cycles with distinct long- and short-term variations. Trends of δ13C coal values changes coupled with the evolution of coal-forming plants may record a gradual increase in paleo-CO 2 (p CO 2) concentration, water-table level changes and the decrease in abundance of Classopollis conifer pollen through Bajocian. This result is in accordance with the published marine carbonate records for this time, with correlation enabled through matching carbon isotope curves from the terrestrial succession at Yuqia and marine records. The similarity of the terrestrial and marine geochemical and floral record is an indication that the observed paleoclimate signal is a global phenomenon. Furthermore, the high-frequency fluctuation of δ13C coal values, along with the coal petrologic variations may record short-term changes of environmental factors (e.g. temperature or humidity/precipitation), especially during intervals when palaeobotanical composition has not fluctuated intensely. • Paleoclimate trends evaluated from terrestrial Northern Qaidam Basin, NW China • Carbon-isotope, petrological and floral record of Bajocian age Yuqia coals revealed • Isotope value distribution indicate coals largely derived from gymnosperm plants • Variations in long- and short- peat deposition cycles record paleoclimate trends • Similarity of marine geochemical and terrestrial record supports global signal [ABSTRACT FROM AUTHOR]